diff --git a/92-tuned.install b/92-tuned.install
index 0f7bdf3..5864eb9 100755
--- a/92-tuned.install
+++ b/92-tuned.install
@@ -5,6 +5,9 @@ KERNEL_VERSION="$2"
 BOOT_DIR_ABS="$3"
 KERNEL_IMAGE="$4"
 
+# skip if systemd-boot is used
+[ "$KERNEL_INSTALL_LAYOUT" = "bls" ] && exit 0
+
 if ! [[ $KERNEL_INSTALL_MACHINE_ID ]]; then
   exit 0
 fi
@@ -32,16 +35,17 @@ for f in `basename "$MACHINE_ID"`-*.conf; do
     continue
   fi
 
-  if [ "${ARCH:0:4}" = "s390" ]; then
-    # On s390(x), the zipl bootloader doesn't support variables,
-    # unpatch TuneD variables which could be there from the previous TuneD
-    # versions
-    grep -q '^\s*options\s\+.*\$tuned_params' "$f" && sed -i '/^\s*options\s\+/ s/\s\+\$tuned_params\b//g' "$f"
-    grep -q '^\s*initrd\s\+.*\$tuned_initrd' "$f" && sed -i '/^\s*initrd\s\+/ s/\s\+\$tuned_initrd\b//g' "$f"
-  else
-    # Not on s390(x), add TuneD variables if they are not there
+  if grep -q '\(\s*grub_\)\|\($grub\)' "$f" && [ "${ARCH:0:4}" != "s390" ]; then
+    # grub generated BLS entries detected and not on s390(x) where zipl is used,
+    # there is high chance that variables in BLS entries will be supported (grub
+    # extension is unsupported by zipl)
     grep -q '^\s*options\s\+.*\$tuned_params' "$f" || sed -i '/^\s*options\s\+/ s/\(.*\)/\1 \$tuned_params/' "$f"
     grep -q '^\s*initrd\s\+.*\$tuned_initrd' "$f" || sed -i '/^\s*initrd\s\+/ s/\(.*\)/\1 \$tuned_initrd/' "$f"
+  else
+    # BLS entries generated by some unsupported tool or on s390x, unpatch TuneD
+    # variables which could be there from the previous TuneD versions
+    grep -q '^\s*options\s\+.*\$tuned_params' "$f" && sed -i '/^\s*options\s\+/ s/\s\+\$tuned_params\b//g' "$f"
+    grep -q '^\s*initrd\s\+.*\$tuned_initrd' "$f" && sed -i '/^\s*initrd\s\+/ s/\s\+\$tuned_initrd\b//g' "$f"
   fi
 done
 popd &> /dev/null